B) herman von helmholtz
The trichromatic color theory<span> began in the 18th century, when </span>Thomas Young<span> proposed that color vision was a result of three different </span>photoreceptor cells<span>. </span>Hermann von Helmholtz<span> later expanded on Young's ideas using color-matching experiments which showed that people with normal vision needed three wavelengths to create the normal range of colors. Physiological evidence for trichromatic theory was later given by </span>Gunnar Svaetichin<span> (1956).</span>
Answer: Desert ecosystems, like all ecosystems, can vary greatly. ... These levels are used to describe ecosystem structure and dynamics. ... of heavy metals, such as mercury and cadmium, in certain types of seafood.
Explanation:
Ecosystems are complex with many interacting parts. They are routinely exposed to various disturbances: changes in the environment that affect their compositions, such as yearly variations in rainfall and temperature. Many disturbances are a result of natural processes. For example, when lightning causes a forest fire and destroys part of a forest ecosystem, the ground is eventually populated with grasses, followed by bushes and shrubs, and later mature trees: thus, the forest is restored to its former state. This process is so universal that ecologists have given it a name—succession. The impact of environmental disturbances caused by human activities is now as significant as the changes wrought by natural processes. Human agricultural practices, air pollution, acid rain, global deforestation, overfishing, oil spills, and illegal dumping on land and into the ocean all have impacts on ecosystems.
Complexity hope this helps
Art of movement refers to a group youthful individuals who use dance to popularize the <span>b-boy culture in various states and outside of the US:
Contributions that can help promote the different art movement:
1. Start sub groups in different regions but all ascribing to the mother group. This way, they can perform with ease in different regions and reach out to more people.
2. Adopt the essence of local cultures. People easily identify themselves with what they are already familiar with.
3. Have a dedicated radio channel. Yes, by having a dedicated radio channel, people will know which platform they can have access to their favorite gigs.
4. Incorporate inter racial members
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